| 摘要 |
The invention relates to a method and an apparatus for determining a field current through a field winding in an electrical machine with a stator (2) and a rotor (4), wherein the electrical machine (1) comprises a field-circuit transformer (7) in order to bring about, by induction of an electrical current on the rotor side, the field current (I DC) with which a field winding (6) is energized in order to generate an excitation magnetic field, having the following steps: - driving on the primary side of the field-circuit transformer (7) in order to bring about a field current (I DC), which is derived from the current induced on the secondary side in the field-circuit transformer (7), in the rotor (4); - measurement of one or more phase currents in one or more primary-side phases of the field-circuit transformer (7); - determination of a maximum value (l peak_measure) depending on the one or more measured phase currents (I1); - determination of the field current (I DC) through the field winding (6) depending on the determined maximum value (l peak_measure). |
